Plural lamp-socket.



R. B. BENJAMIN.

PLURAL LAMP SOCKET.

l APPLIUATION FILED 916,909, AUG 25 1906 Patented Mar. 30, 1909.

MHEETSAHEBT 1.y $65110 3.9 70 lo fill/lll] R. B. BENJAMIN.

PLURAL LAMP SOCKET.

APPLICATION FILED AUG. 25, 190s.

Patented Mar. 30, 1909.

2 SHEETS-SHEET 2.

UNITED STATES FATFQNI FFICE.

REUBEN B. BENJAMIN, OF CHICAGO, ILLINOIS, ASSIGNOR TO BENJAMIN ELECTRIC MANU- FACTURING COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

PL'RAL LAMP-SOCKET.

To all whom it may concern:

Be it known that I, REUBEN B. BENJAMIN, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented new and useful Improvements in Plural Lamp Sockets, of

which the following is a full, clear, concise,

and exact description, 'reference being had to the accompanying drawing, forming a part of this specification.

My invention relates to improvements in plural lamp sockets and consists of novel features of construction therein.

One object of my invention is to provide a plural lamp socket which is simple, strong, economical to manufacture, and of neat appearance.

Another object is to provide a plural lamp socket in which the base is removably attached to the back plate.

A further object is to provide a construction in a plural lamp socket which will permit the clamping of the lamp shade in position between the base and back plate.

Still another object is the provision of means in connection with the plural lamp socket, whereby the amount of light desired may be conveniently obtained by switching in or out of service either a single central lamp or a group of lamps in a circle, or all the lamps combined.

Other objects and advantages willbe apparent from the following description, and the characteristic features and scope of the invention will be fully understood therefrom.

Referring to the drawings, in which like reference characters refer to like parts throughout the several views: Figure 1 is a vertical sectional View, the section being taken on the dotted line 1 1 of Fig. 2; Fig. 2 is a view taken on the dotted line 2-2 of Fig. 1, and also shows diagrammatically the manner of connecting conductors between the switch and the lamp contacts; Fig. 3 is a top plan view of the plural lamp socket; Fig. 4 is a detail view of the spring-pressed plunger carried in ears which depend from the annular ring which is mounted on the top of the base; Fig. 5 is a detail view which shows an ear depending from the annular ring; Fig. 6 is a detail of a lamp shell; Fig. 7 is a detail of the center contact for the center lamp; and Fig. 8 is Specification of Letters Patent.

Application :tiled August 25, 1966.

Patented March 30, 1909.

Serial No. 332,040.

a detached view in section showing the manner of attaching the back plate to the base.

In the form of construction for a five lamp cluster embodying my invention as shown in the drawings, the casing or cover consists of metal., preferably iron or steel, provided with the coatings 2 and 3 of ictile material on the exterior and interior thereof, and having projecting sleeves 4, an annular interior pocket 5, and near the upper edge the inwardly and thence upwardly extending lug 6.

I-Ieretofore a fiber sheath or shield has been attached to the interior of the casing for lamp sockets to insulate said casing from possible contact with the line wires and interior contacts in the socket. It is diiiicult to secure such insulation in place, and besides it is apt to collect moisture and fail in its function. To overcome the disadvantages and defects which result from the use of such insulation, I provide the interior, and preferably, also, the exterior of the casing, with a coating of lictile material in the form of an enamel, by which means the casing is absolutely prevented from becoming a part of the lamp circuit even though the interior connections of the cluster should become displaced in position. A very great advantage resulting from, the use of enamel on the casing is that tie casing is protected from deterioration by corrosion. The enamel may be of any suitable color, and if white, serves to reflect more light.

The casing is removably associated with the insulating base 7 by the means to be iereinafter specified. With a View to lightness and economy of material, the base is constructed of porcelain or like material hollowed out in its middle back portion 8. The openings 9 therein are for the passage of the conductors which are connected to the bind ing screws on the terminal plates as hereinafter described.

Upon the back part of the base, the annular ring 1() is mounted, being secured in position by the screw bolts 11 (Fig. :2), whose heads are conntersunk in the rino' 10, so as to be flush with the surface thereof, and which bolts extend through the base, threading into the nuts l?) in the niches 12. A suitable numcarry pins 15 which co-act with suitable slots which extend from the upper edge of the up;

wardly 'extending ,portion of the flange 6 on i the casing, to form a bayonet joint', by which mea-ns the casing may be removably attached in position 'on the base.

A spring-'pressed 'plunger 16, which` passes through an opening in the base and is carried by the onpositely disposed 'ears i7, which depend from the ring 10, locks the casing in position. rthe head 158a 'of the plunger' lits into an opening in the casing and may be removed therefrom by pressing it inwardly and turning the casing in the nnlocking direction, or it may be rounded off and shaped so that.I it will be' moved out of the opening by the casing when a sudden twist is given the latter. In the niche 20 in the base a metallic terminal plate 18 is suitably secured in position as by screws 19 and carries the binding screw 23 and springmetal contact piece, which is formed to have the portion 2 1 resting thereupon and in con-- tact therewith, and a portion 22 which is bent forwardly on the underside of the block.

kThe spring Contact member 24, provided with .tongues 25 which serve as center contacts for a circularly arranged series of lamps, is carried upon the annular terminal plate 26, which latter is secured to the bottom face of the base by any suitable means, as screws 27, and provided with the binding screw 28.

The `base is removably att-ached to the back plate 29, which is formed so that the lamp shade Bet may be clamped in position between it `and the base when the latter is attached. The plate may be secured by screws directly lto the wall or ceiling, but ,is shown provided with a threaded socketr 30 for the reception of a conduit pipe in the usual manner. The annular downwardly pressed portion B1 of the plate carries the small screw bolts 32, which thread into openings from the underside of the plate. To att-ach the base to the back plate it is placed against the back plate so that the heads of the screwbolts 32 thereon pass into the enlarged portion of the slots 35, which slots extend through the plate 10 into the porcelain of the base, and the base is then turned to bring the narrow portions of the slots in the plate 10 over the heads of the screw-bolts.

To permit access to the screw-bolts from below when the base is in position on the back `plate so .that the screw-bolt may be tightened to hold the shade firmly clamped in position, the base isxcut away as shown at 35. A suitable naked conductor wire 37, sprung in position in the pocket 5 on the casing, provided with an inwardly extending portion 4-2 which 'moves onto the spring contact 'piece 2,2 when the casing is attached to the base. vThe wire' 37 is in engagement with the `(':Qont'ac't members 38 of the lamp shells 39 l "eh are arranged in the sleeves 1l. The lamp shells are provided with limbs 40 at their lower part, which are secured in common to the plate 41, whereby the shells are held lrigidly in position. l

To make provision for the use ofl -a central lamp in the cluster, the lamp shell 4t2 in. the sleeves 43 is preferably secured in a suitable i'nanner to the flange ist on the plate 41; and a terminal plate 45 (F ig. 2) provided with the binding screw 16 and springjtongue 47 f or the center' contact is suitably secured to the bottom of the base.

Another feature of my invention consists of the switch and arrangement of 'circuits shown diagrammatically in Fig. 2, by the employment of which am enabled to obtain conveniently the amount of ylight desired from the cluster. Heretofore, it was customary to use either an individual key for each lamp, whereby the lamps inv a cluster could be turned out individually, or to make arrangements for turning them all out together by means of a wall or chandelier switch, or else, as has been done in some instances, the lamps in a cluster have been divided intot-wo or more groups in a circle and operated by a suitable switch, whereby the closing of a 'circuit through one of the lamps of the circle which formed a group by itself, might be effected. The one ylamp not being centrally located could not give an even distribution of light, and in order to get anything` like an even distribution it was necessary to have a group of lamps with two or more lamps burning. ln the plural lamp socket of my invention a lamp is arranged centrally in the cluster, and the circuit arrangement is such that it alone, or the group of lamps in the ycircle alone, or both the central lamp and the group of lamps in the circle, may be switched into service to obtain the desired amount of light. The advantage of lthe above arrangement is obvious; in the first place, three degrees of light may be obtained, which can be regulated in accordance with the candle power of the lamps used; thus the one lamp inthe center (which may be from 4 to 50 c. p.) making' a one light fixture when its K light is sufficient. Again, the 'amount of light may be increased by turning out the center lampv and lighting all the lamps in the circle. This gives an equal distribution in all directions, the lamps all being in. one circle and equally spaced. `And again, all lamps in the cluster may be lighted at the same time.

4lt will be obvious that the arrangement of lamps and circuits therefor, as above described, is of advantage also in that it permits the insertion of an attachment'plug in the center lamp socket for an electrically driven fan or like device without interfering with symmetrical distribution of light by the lamps in the remaining sockets.

The circuit arrangement, to accomplish group lighting as described, may be as follows; One ot' the service wires 55 is secured to the terminal plate 18 by means of the binding screw 23, and is thus electrically connected to the lamp shells. The other service wire 5l connected to the conveniently located switch 48, which is pivoted at 49 and adapted to be moved over the contact buttons 50, 5l, 52 and 53. Conductors 56 and 57 are connected respectively between the contact buttons 5() and 51 and the terminal blocks 45 and 26, and the contact buttons 50 and 53 are electrically connect ed, as are also the contactbuttons 51 a'nd 52.

lt will readily be seen that when the switch arm 48 is moved to contact button 50 the circuit is closed between the opposite service wires through the center lamp only, and when the switch arm is moved to contact button` 51 the circuit is closed between the opposite service wires through the lamps arranged in the circle; again, when the switch arm is moved to the contact buttons 52 and which are in line with each other and the pivot of the switch arm, the circuit is closed between the opposite service wires through all the lamps in the cluster, for the reason that the contact button 52 is electrically connected to contact button 51, and contact button is electrically connected to contact button 50.

ln operation, the base may be removed and then replaced in the manner already mentioned, to clamp a lamp shade in position; and the casing may be removed from the base to permit attaching the conductors to the binding screws, and when replaced the portion Ll2 of the naked wire 37 in the casing engages the spring contact 22.

lith the wires of opposite potential connec'ted to the binding screws 23, and 28 and etti, respectively, the current is traced as follows: from the service wire 55 to the binding screw 23, to the terminal plate 18, to the spring contact piece 22, to the naked conducting wire 37, thence to the individual lamp shells, and through those lamps whose center contacts are in closed circuit th rough the switch a8 with the service wire 54.

l de not wish to be understood as limiting myself to the details of construction precisely as set tor-th, since obvious modilications will occur to a person skilled in the art.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is:

l. In a plural lamp socket, a casing, a group of circularly arranged lamp sockets carried by the casing and a centrally disposed lamp socket, means :tor connecting one of the contacts of said centrally disposed socket with one of the contacts of all the other sockets, and means for connecting to gether the opposite contacts of all the circularly arranged sockets, the opposite contact for said centrally disposed socket being isolated.

2. ln a plural lamp socket, the combination with. an insulating base, of a casing, a group of circularly arranged shell contacts carried by said casing, and insulated therefrom, a centrally disposed shell contact carried by said casing, means for electrically connecting together all of said shell contacts, a binding terminal carried by said base with which said connecting means makes contact when said casing is in position upon said base, center contacts carried by the base and corresponding with the respective circularly arranged shell contacts, a binding terminal Ytor said contacts, an isolated center contact for association with said centrally disposed shell contact, and a binding terminal for said isolated contact.

3. ln a plural lamp socket, an insulating base, a casing having a plurality of circularly arranged openings and a centrallydisposed opening, sleevessecured to said casing surrounding said openings, a threaded shell in each of said sleeves, means carried by the casing connecting together all of said shells, a center contact on said base correspending`- to each ol said shells, a binding terminal fer the centrally disposed contact, a second binding terminal for all of the eircularly arranged center contacts, a Vthird binding terminal carried by the base, and means for establishing electrical connection between said third terminal and the threaded shells when said casing is in place In witness whereof, I have hereunto subscribed my name in the presence of two witnesses.

REUBEN B. BENJAMIN.

Witnesses EMM; A. OLSEN, HARRY A. VARNELL. 

